Now that we know the Fire TV Stick’s USB port is not just for power, I tried every way I could think of to get a USB keyboard or mouse to work with the device. You can see a sample of my test setup above with some of the OTG and non-OTG cables I tried without any success. I tried both with and without a powered USB hub with every cable and configuration. There was never a sign that the Fire TV Stick recognized a connected peripheral. This leads me to believe the Fre TV Stick kernel or OS is deliberately set to remain in USB slave mode and not enter USB host mode. For anyone interested, here are the cables/adapters I tired: included micro USB cable, OTG cable w/ power, Femnale / Male adapter, Sanoxy OTG Cable, StarTech OTG Cable, Generic OTG Cable, and various non-OTG cables I had.